CANBERRA (NYTIMES) – It is a scene that has played out countless times across the swamps and wetlands of northern Australia: A family of feral pigs went down to the water’s edge to drink.

Just when the pigs are at their most vulnerable, the world’s largest crocodile species erupts from its camouflage in the water, sending piglets flying in a ferocious display of teeth and power. Even an adult pig, which can weigh up to 70kh, doesn’t stand a chance.

“Crocodiles eat whatever is easiest, and feral pigs are the perfect size,” said Mariana Campbell, a researcher at Charles Darwin University in Australia who studies saltwater crocodiles in the country’s north.

“They’re pretty lazy hunters. If you’re a crocodile, what is easiest? You stay near the bank and wait a few hours for a pig? Or you go and hunt for a shark, an animal that can swim five times faster than you?”

Frank Mazzotti, a crocodile and alligator expert from the University of Florida, agreed.

“A pig coming down to the water’s edge is like ringing the dinner bell,” he said.

Some scientists hope that the encounters between the crocs and the swine may be the first sign that the feral pig, an invasive species that has done great damage to Australia’s wild terrain, has finally met its match.

The instances may also help to explain why crocodiles are doing so well, according to a recent study that Campbell and other researchers published in the journal Biology Letters.

The saltwater, or estuarine, crocodile has lived for millions of years in Australia. The feral pig arrived in Australia with the first European settlers in the late 18th century.

One is Australia’s largest apex predator that came close to extinction in the early 1970s. The other has spread across nearly 40 per cent of Australia’s land mass, and conservative estimates suggest that there may be 24 million in the country.

Scientists blame feral pigs and other invasive species for widespread habitat loss and for Australia having the world’s highest rate of mammal extinctions.